The long term goal of this proposed research project is to establish a dynamic spatio-temporal source imaging methodology that is able to image and localize epileptogenic brain from noninvasive high resolution electroencephalogram (EEG) measurements to aid surgical planning in epilepsy patients. Epilepsy is one of the most common neurological disorders, affecting 50 million people worldwide. In approximately 30% of these patients the seizures are not controlled by any available drug therapy, and surgery is a viable option for partial epilepsy. Localization and imaging of epileptogenic brain responsible for seizures is of paramount importance for successful epilepsy surgery. Currently, definite localization of epileptogenic zone is performed from invasive intracranial EEG. In the proposed research project, we propose to develop novel noninvasive source imaging methods that promise to localize and image source extent corresponding to epileptogenic zone, from interictal spikes and high frequency oscillation activities that can be measured using high density electrode array. We also propose to validate rigorously the proposed source imaging techniques in a group of epilepsy patients undergoing intracranial EEG recordings and surgical resection. The specific aims are: Aim 1) Development of EEG source extent imaging methods for imaging epileptogenic brain. Aim 2) Development of high-frequency source imaging methods for imaging epileptogenic brain. Aim 3) Validation of source imaging methods from intracranial recordings and surgical resections in partial epilepsy patients. The successful completion of the proposed research promises to lead to establishment of a disruptive technology to localizing and imaging of epileptogenic brain from noninvasive high resolution EEG, which can significantly advance state-of-the-art of management of intractable epilepsy. The development of such novel technology would benefit numerous patients suffering from partial epilepsy and the healthcare system.